The present disclosure relates to changing video playback rate and playback time in a digital video editing system.
Various time remapping solutions exist to map source media frames to output media frames. Time remapping (also known as variable speed playback) involves dynamically controlling the speed of a video clip and alternating between a range of speeds in both forward and reverse playback, as well as freeze frames. Typically, a time remapping software feature uses a speed/velocity graph, where control points are set and Bezier-like curves dictate the playback speed and direction between the control points. Each control point can be moved in the graph, allowing the video editor to control the playback rate at that control point. After each such movement of a control point, the Bezier-like curves connecting the control points are recalculated, thereby determining the playback speed (and direction) between the control points. Furthermore, to help distinguish between various playback rates, at least one user interface for a time remapping feature has included straight, vertical tic marks that are spaced closer together or further apart to indicate deceleration or acceleration, and red tic marks to indicate reverse playback direction.